Note: Javascript is disabled or is not supported by your browser. For this reason, some items on this page will be unavailable. For more information about this message, please visit this page: About CDC.gov.

Metabolic rate of animals can be affected by a variety of toxic agents. Virtual instrument software was developed to capture and display data provided by a modified direct calorimeter. The calorimeter system was evaluated by examining four groups of rats (n=6) injected with thyroxine(T4) or solvent alone. Half of each group was exposed to ozone (2 ppm for 3 hours) or air. Breathing rates in addition to metabolic rates were measured pre-exposure, immediately post-exposure and 18 hours post-exposure. Metabolic rates were computed following equilibration which occurred in ten to twenty minutes. The calorimeter system provides non-invasive, reproducible results which can be used to evaluate an animal's metabolic response to toxic materials. In addition, the system displays and saves the data in real time and is easily operated.